Illuminating device

ABSTRACT

Disclosed is a lighting device which comprises: an optical member comprising a protruding optical pattern forming a gap with an adjacent layer; at least one light emitting unit inserted into the optical member; and a resin layer formed on the optical member and the at least one light emitting unit, whereby it is possible to obtain an effect that the shapes of light change depending on the viewing angle when viewing the light source by producing various protruding optical patterns, an effect that the whole thickness can be reduced, and an effect that the degree of design freedom can be enhanced when designing products thanks to an enhanced flexibility.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/363,789, filed Nov. 29, 2016; which is a continuation of U.S.application Ser. No. 14/587,774, filed Dec. 31, 2014, now U.S. Pat. No.9,541,696, issued Jan. 10, 2017; which is a continuation of U.S.application Ser. No. 13/686,675, filed Nov. 27, 2012, now U.S. Pat. No.8,960,977, issued on Feb. 24, 2015; which claims the benefit under 35U.S.C. § 119 of Korean Patent Application No. 10-2012-0087769, filed onAug. 10, 2012; all of which are herein incorporated by reference intheir entirety.

BACKGROUND OF THE INVENTION Field of the Invention

Embodiments of the present invention relate to a lighting device, and inparticular to a lighting device structure which makes it possible tomake the whole thickness thinner as such to obtain a high illuminatingefficiency in such a way to remove a light guide plate and makes itpossible to obtain an effect that the shape and a 3D effect of lightchange by forming a protrusion optical pattern.

Description of Related Art

The LED (Light Emitting Diode) device is directed to converting anelectric signal into infrared ray or light using the natures of acompound semiconductor. Different from a fluorescent lamp, it does notuse any harmful substances such as mercury, which results in lessenvironment contamination, along with an advantage that service life islonger as compared to a conventional light source. It also consumes lowelectric power as compared to a conventional light source, andvisibility is good thanks to a high color temperature and no glaring.

The lighting device is currently changing from a type that aconventional incandescent lamp and a conventional fluorescent lamp areused as a light source to a type that a LED device is used as a lightsource. In particular, there is provided a lighting device whichperforms a plane light emitting function by using a light guide plate asdisclosed in the Korean patent publication number 10-2012-0009209.

The light guide plate is used as a necessary element of the conventionallighting device 1; however it has a limit in making a thinner productowing to the thickness itself of the light guide plate. Since thematerial of the light guide plate is not flexible, it cannot be appliedto the external housing 50, etc. which has curved surfaces, so theproduct design and the design changes are not easy.

SUMMARY OF THE INVENTION

Accordingly, embodiments of the present invention are made to resolvethe problems encountered in the conventional art. It is an object of theembodiment of the present invention to provide a lighting device whichmakes it possible to make the whole thickness thinner.

It is another object of the embodiment of the present invention toprovide a lighting device which provides a high degree of freedom whendesigning a product by allowing a lighting device itself to haveflexibility at an upper portion of a PCB or a lower upper of a secondoptical member for thereby enhancing the reliability of a product.

It is further another object of the embodiment of the present inventionto provide a lighting device which provides a geometric optical pattern.

To achieve the above objects, there is provided a lighting devicecomprising: an optical member comprising a protrusion optical patternforming a gap with an adjacent layer; at least one light emitting unitinserted into the optical member; and a resin layer formed on theoptical member and the at least one light guiding unit.

Effects of the Invention

The embodiment of the present invention provides an effect that thenumber of light emitting units is reduced, and the whole thickness of alighting device can be made thinner by removing a light guide plate andguiding light using a resin layer.

In the embodiment of the present invention, the lighting device isformed using a flexible PCB and a resin layer so as to obtainflexibility, thus enhancing a degree of freedom in a product design.

An optical member with a protrusion optical pattern formed between aresin layer and a reflection member is provided, so an effect that theshape and a 3D feeling of light change depending on a viewing angle. Aneffect that the shape of a protrusion optical pattern changes can beobtained by forming an adhering pattern between the optical member andthe reflection member. In addition, the lighting device with an enhancedaesthetic feeling can be provided, and can be also applied to variousfields.

In addition, since the embodiment of the present invention provides areflection member and a reflection pattern which define a structureconfigured to efficiently reflect the light emitted from the lightemitting units, thereby maximizing luminance along with the enhancedreflectivity of light and providing the uniform plane light source.

A first optical substrate and a second optical substrate each having anoptical pattern are provided in the embodiment of the present invention.An air gap is formed at the adhering layer, thus removing thegenerations of hot spots and a blackening phenomenon which occur atlight shield pattern portions, and the reliability of the elementsadhered to the adhering layer can be enhanced, and the lighting devicewith no significant differences in optical characteristics can bemanufactured, and a precise alignment between elements can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view illustrating major portions of a lighting deviceaccording to an embodiment of the present invention.

FIG. 2 is a view illustrating a structure in which a bead and an opticalmember are added to the lighting device according to the embodiment ofthe present invention illustrated in FIG. 1.

FIG. 3 is a view illustrating a structure in which an optical member andan optical sheet are added to the lighting device according to theembodiment of the present invention illustrated in FIG. 1.

FIG. 4 is a schematic view illustrating a structure in which thelighting device according to the embodiment of the present invention isapplied to a headlight for a vehicle.

FIG. 5 is a view illustrating an actual operation state image of thelighting device according to the embodiment of the present invention.

DESCRIPTION OF SPECIFIC EMBODIMENTS

The embodiments of the present invention that an ordinary person skilledin the art can implement will be described with reference to theaccompanying drawings. The embodiments in the specification and theconstructions shown in the drawings are provided as a preferredembodiment of the present invention, and it should be understood thatthere may be various equivalents and modifications which couldsubstitute at the time of filing. In addition, when it comes to theoperation principle of the preferred embodiments of the presentinvention, when the known functions or functions are seemed to makeunclear the subject matters of the present invention, they will beomitted from the descriptions of the invention. The terms below aredefined in consideration of the functions of the present invention, andthe meaning of each term should be interpreted by judging the wholeparts of the present specification, and the elements having the similarfunctions and operations of the drawings are given the same referencenumerals.

The present invention is basically directed to a lighting device using aLED as a light source, which features in that a light guide plate isremoved, and a resin layer is formed instead, and an optical member witha protrusion optical pattern between a reflection member and a resinlayer is further provided, which makes it possible to be applied tovarious applications thanks to a geometric shape, not a simple planesurface light emission.

The lighting device according to the embodiments of the presentinvention can be applied to various lamp devices which necessitatelighting for example a lamp for a vehicle, a lighting device at home anda lighting device for the purpose of industry. When it is applied to thelamp for a vehicle, its application includes a headlight, an indoorlighting in a vehicle, a door scuff, a rear lighting, etc. The lightingdevice according to the embodiments of the present invention can beapplied to a backlight unit field which is generally applied to a liquidcrystal display. The present invention may be applied to all thelighting-related applications which have been already developed and thencommercialized or which would be implemented as the technology advances.

FIG. 3 is a view illustrating the major portions of a lighting deviceaccording to an embodiment of the present invention.

Referring to FIG. 3, a lighting device 100 a according to the presentembodiment of the invention may comprise an optical member 210 with anoptical pattern, and at one light emitting unit 130 inserted into theoptical member 210. That is, the optical member 210 and the lightemitting units 130 may form an arrangement structure in which the lightemitting units pass through the optical member 210. Moreover, thelighting device may further comprise a resin layer 150 formed on theoptical member 210 and the at least one light emitting unit 130.

Reviewing the configuration of the lighting device according to thepresent embodiment of the invention, which is embodied based on thebasic elements, with reference to FIG. 3, the lighting device accordingto the present embodiment of the invention may further comprise aprinted circuit board 110 on which the light emitting units are mounted.

Specifically, the lighting device according to the present embodiment ofthe invention may be configured such that the least one light emittingunit 130, and an optical member 210, which is formed in a structure inwhich the light emitting units are inserted, are sequentially formed,and may comprises a resin layer that buries the light emitting unit 130and guides the emitting light in a forward direction.

In the above explained structure, there may be further provided areflection member 120. The optical member 210 may comprise a means whichperforms an optical operation, for example, a light guide, a lens, awave guide and the like. FIG. 1 illustrates that the optical member 210according to one embodiment has a laminated structure composed of two ormore layers without being limited to this.

The PCB 110 is a typical substrate formed as a circuit pattern isprinted on a substrate. In the present invention, The PCB 110 may beformed of a flexible PCB (FPCB) so as to obtain flexibility.

The light emitting unit 130 is directed to emitting light as it isaligned in one or more numbers on the FPCB 110. The light emitting unit130 of the present embodiment may be formed of a side view type lightemitting diode. When the side view type light emitting diode is used,light transmitted in an upward direction is transmitted though the resinlayer, so that brightness can be more easily adjusted compared to a casein which a top view type light emitting diode is used. Furthermore, itis advantageous that a thickness of the resin layer laminated in astructure in which the light emitting unit 130 is buried can be madethinner, and the uniformity of light in light emitting surface of aplate-like structure can be obtained thanks to the resin. That is, whenthe top view type light emitting diode is used, the light has an upwarddirection, and in this case, a range in which the light spreads outaround the light emitting diode is narrow. On the contrary, in the caseof the side view type light emitting diode, the light spreads out widelyto a side so that a light distribution property and a property forsecuring the intensity of light can be improved, thereby allowing thenumber of light sources to reduce. That is the light emitting diode withthe structure in which the light is emitted toward the side, not movestraight upwardly can be used as the light emitting unit 130 accordingto the present embodiment.

Moreover, the light emitting unit according to the present embodiment ofthe invention may be implemented in a structure which is buried in theresin layer. Also, when the light emitting unit is formed in thestructure which is buried in the resin layer, the resin layer and thelight emitting unit are integrally formed, so that the structure issimplified. Furthermore, in a case where the light emitting device suchas the LED is used as the light emitting unit, a refractive index of afluorescent silicon substance and the resin layer disposed at the frontof the LED light device varies. That is, the intensity of light emittedfrom the LED is increased by a difference in refractive index comparedto the case in which the light is directly emitted to the air.

Specifically, considering the matter that the refractive index of thefluorescent silicon substance is generally 1.5 and the refractive indexof the resin layer is 1.47, as a difference in refractive index of amedium which light passes through reduces, a critical angle increases.As a result, light loss generated inside the LED can reduce and thelarge intensity of light can be secured.

Also, when the light emitting unit is formed in the structure into whichthe resin layer is inserted, a thickness of the whole lighting devicecan be made thinner relatively compared to the conventional structure inwhich a light guide plate is arranged on an upper surface, and since thelight emitting unit has a structure in which light is directly emittedinto the optical member, it is advantageous that the loss amount oflight can be reduced, and thus the efficiency of light can be increased.

In the lighting device 100 a according to the present embodiment of theinvention, the light emitting unit 130 composed of the side view typelight emitting diode is disposed in a direct type, and the number of thewhole light emitting units can be reduced by diffusing and guiding thelight in an upward direction by utilizing the resin layer, and the totalweight and thickness of the lighting device can be significantlyreduced.

The resin layer 150 is formed on the upper portions of the opticalmember 210 and the light emitting unit 130, and the resin layer 150serves to guide the light from the light emitting unit 130 to diffuseforward. In other words, the resin layer 150 is configured to bury thelight emitting unit 130, thereby spreading the light emitted from thelight emitting unit 130 in a lateral direction.

The resin layer 150 according to the present embodiment may be made froma resin material which can diffuse light. For example, the resin layer150 according to the present embodiment is made from an ultravioletcurable resin containing oligomer. More specifically, the resin layer150 is made from a resin containing urethane acrylate oligomer as a mainmaterial. A resin mixed with urethane acrylate oligomer and polyacrylpolymer type may be used. Of course, a monomer mixed with IBOA(isobornyl acrylate), HPA (hydroxylpropyl acrylate), 2-HEA(2-hydroxyethyl acrylate), etc. which are low boiling point dilutiontype reaction monomers may be further contained. As an additive,photoinitiator (1-hydroxycyclohexyl phenyl-ketone, etc.) or antioxidantmay be mixed. The above mentioned examples are provided only forillustrative purposes. In addition thereto, a resin layer 150 of thepresent invention could be formed using a certain resin which iscurrently under developments and used or all kinds of resins havinglight diffusion functions which will be developed in the future as thetechnology advances.

According to the present embodiment of the invention, thanks to thepresence of the resin layer 150, it is possible to significantly reducethe thickness which used to occupy a lot of areas in the conventionallight guide plate, and the product can be made thinner and compact. Thematerial is flexible, so it can be easily applied to curved surfaces. Adegree of freedom in term of the designs of products can be enhanced,and the lighting device according to the present embodiment of theinvention can be well applied to flexible displays.

The reflection member 120 is formed on the upper surface of the printedcircuit board 110, and has the structure into which the light emittingunit 130 is inserted. Since the reflection member 120 according to thepresent embodiment is made from a material with a high reflectionefficiency, the reflection member serves to reduce light loss byreflecting the light emitted from the light emitting unit 130 upward.The reflection member 120 may be formed in a film shape and may beformed by including a synthetic resin which spread-contains whitepigment so as to implement the natures helping promote the reflectionand diffusion of light. For example, the white pigment may be titaniumdioxide, aluminum oxide, zinc oxide, carbonate, barium sulfate, calciumcarbonate, etc, and the synthetic resin may be polyethyleneterephthalate, polyethylene, naphthalate, acryl resin, polycarbonate,polystyrene, polyolefin, cellulose acetate, weatherproof vinyl, etc.,but such material is not limited to them.

A reflection pattern 121 may be formed on the surface of the reflectionmember 120. The reflection pattern 221 serves to scatter and disperseincident light to make sure that the light is uniformly transmitted intothe upper portion. The reflection pattern 121 can be formed by printingon the surface of the reflection member 120 using a reflection ink whichcontains one among TiO₂, CaCO₃, BaSO₄, Al₂O₃, Silicon, PS, etc., andsuch method is not limited thereto.

In particular, when the reflection pattern 121 is implemented in aprinting structure using the reflection ink, in consideration of aportion where a high reflectivity is required and a portion where a lowreflectivity is required depending on the arrangement of the lightsource, a design of the optical pattern can be easily performed.Moreover, in a case where the reflection ink containing the aforesaidmetal material is applied to the reflection pattern 121, it isadvantageous that the reflection pattern 121 shows an excellentreflection efficiency compared to that of a general reflection patternwhich is implemented in a protruding structure with regard to astructural aspect.

The reflection pattern is formed in a structure formed of a plurality ofprotruding patterns. So as to enhance the reflection and diffusioneffects of light, it can be formed in a dot pattern shape, a prismshape, a lenticular shape, a concave lens shape, a convex lens shape ora combination of at least two shapes, but it is not limited to them. Inaddition, a cross section of the reflection pattern may be formed invarious shapes such as a triangle shape, a quadrangle shape, asemi-circular shape, a sine wave shape, etc.

The optical member 210 may be disposed on an upper surface of thereflection member 120, and may have a structure in which the opticalpattern is formed on a surface being toward the reflection member 120.In a case where the resin layer is formed on the reflection member 120,and the protruding patterns of the optical pattern move upward, it isproblematic that a pattern function may be lost because the resin entersgaps between the prism patterns.

Also, in a case where the optical pattern is formed on the surface whichcomes into contact with the reflection member, the light reflected atthe reflection member may be immediately scattered by the opticalpattern so that an advantageous effect can be implemented in light ofthe efficiency for light utilization.

The optical pattern of the optical member 210 may be formed on a surfaceopposite to a surface which comes into contact with the resin layer 150.

At this time, the optical member 210 may be formed of any one of a prismsheet having a plurality of unit prism lens patterns, a micro lens arraysheet and a lenticular lens sheet, or a combination formed of at leasttwo of them. A difference in lens patterns of the optical member has itsmeaning in light of the matter that a light emitting path of athree-dimensional structure according to the present embodiment of theinvention can be variously designed thanks to the difference.

As shown in the drawings, with the aid of the optical pattern, a gap 230is formed between the optical member 210 and the reflection member 120,and an adhering pattern 220 is formed in a shape corresponding to theoptical pattern for the purpose of adhering the optical member 210 andthe reflection member 120. According to the present embodiment, theadhering pattern 220 is formed on the reflection member 120. The gap 230working as an air layer is not formed at the portion where the adheringpattern 220 is formed. In particular, in a case where the adheringpattern 220 is adhered over the whole surface using a double-sidedadhesive without the air layer, the appearance can be contaminated, anda 3D effect can be reduced because the air layer does not exist. Also,the portion where the adhering pattern exists has an excellent adhesioneffect and a difference in reflective index compared to the portion ofthe air layer, which is formed at the portion where the adhering patterndoes not exist. Thus, it is advantageous that various design effects informing three-dimensional light can be implemented.

As such, since the lighting device comprises the optical member 210 suchas a prism sheet, etc. where the optical pattern is formed, not a simpleplane surface light emission, a geometric optical pattern can be formed,and the shape and 3D feeling of the light can change depending on theviewing angle.

At this time, the intensity of light can be adjusted by forming apattern on the reflection member 120 using a reflection ink. The shapeof the protruding optical pattern can be changed using the adheringpattern 220 formed between the reflection member 120 and the opticalmember 210.

FIG. 2 is a view illustrating a structure 100 b in which beads and anoptical member are added to the lighting device according to theembodiment illustrated in FIG. 1.

Referring to FIGS. 1 and 2, a plurality of light diffusers 151 eachhaving pores (or gaps) may be further contained in the interior of theresin layer 150 according to the present embodiment of the invention ina mixed form or a diffused form. The light diffusers 151 server toenhance the reflection and diffusion of light. For example, when lightoutputted from the light emitting unit 130 is inputted into the lightdiffusers 151 in the interior of the resin layer 150, the light isreflected by the pores of the light diffusers 151 and transmits andfocuses, so the light emits in the upward direction of the resin layer.The light diffusers 151 may be implemented of a bead structure as oneexample.

When a lighting device 100 b according to another embodiment of thepresent invention as illustrated in FIG. 2 may further include a secondoptical member 290 in an upper portion of the resin layer 150.

In a case where the second optical member 290 as the structureillustrated in FIG. 2 is formed in the lighting device according to thepresent embodiment, the light diffused and focused at the resin layeremits to the second optical member 290. At this time, the reflectivityand diffusion rate of the light increase thanks to the light diffusers151, so the light intensity and uniformity of the emitting lightsupplied to the second optical member 290 are enhanced, and consequentlythe luminance of the lighting device can be enhanced.

The second optical member 290 may include a means, which performs anoptical operation, for example, a light guide, a lens, an opticaldiffusion layer and the like. In FIG. 2, the second optical member 290according to the present embodiment is illustrated as an opticaldiffusion layer, but it is not limited to this.

Also, the contents of the light diffusers 151 can be properly adjustedso as to obtain a targeted light diffusion effect. In more details, itcan be adjusted within a scope of 0.01-0.3 weight % as compared to thewhole resin layer 150, but it is not limited to this. The light emittingin the lateral direction from the light emitting unit 130 can bediffused and reflected by way of the resin layer 150 and the lightdiffusers 151 and can travel upward. The light diffusers 151 may be madefrom one among silicon, silica, glass bubble, PMMA, urethane, Zn, Zr,Al₂O₃, and acryl. The diameter of each light diffuser 151 may be in ascope of 1 μm to 20 μm, but it is not limited to this.

The lighting device 100 b according to the present embodiment of theinvention may be implemented in a structure by further comprising thesecond optical member 290. In this case, the second optical member 290is formed on the upper portion of the resin layer 150 while ensuringthat the light outputted via the resin layer 15 can concentrated. Thesecond optical 290 is generally made from an acryl resin, but it is notlimited thereto. All kinds of materials can be used as long as suchmaterials have light collection functions like high transmission plasticsuch as polystyrene (PS), poly methyl metacrylate (PMMA), circularolefin copoly (COC), poly ethylene terephthalate (PET), resin, etc.

As not shown in the drawings, the reflection pattern may be formed at alower portion of the second optical member 290. Here, the reflectionpattern represents that protruding patterns are uniformly ornon-uniformly arranged to make sure that the externally emitting lightcan have geometric patterns by reflecting and diffusing the inputtinglight. The above mentioned reflection pattern is formed in a structureformed of a plurality of patterns. So as to enhance the reflection anddiffusion effects of light, it can be formed in a prism shape, alenticular shape, a concave lens shape, a convex lens shape or acombination of at least two shapes, but it is not limited to them. Inaddition, the cross section of the reflection pattern may be formed invarious shapes such as a triangle shape, a quadrangle shape, asemi-circular shape, a sine wave shape, etc. It can be configured in astructure which could change the size or density of each patterndepending on a distance from the light emitting unit 130.

The reflection pattern according to the present embodiment may be formedby directly processing the second optical member 290, but it is notlimited thereto. All kinds of possible methods that have been developedor are under developments or will be developed in the future can be usedincluding a method that a film having regular patterns is attached tothe second optical member 290.

A first spacing part 280 may be formed between the second optical member290 and the resin layer 150. At this time, thanks to the presence of thefirst spacing part 280, the uniformity of light supplied from the secondoptical member 290 can be enhanced. Consequently, the present inventioncan have an effect that the uniformity of light diffused and outputtedvia the second optical member 290 can be enhanced and an effect that theuniform plane surface light emission can be obtained. In an attempt tominimize the deviations of light which has passed through the resinlayer 150, a thickness H1 of the first spacing part 280 may be formed ina range of 0 to 20 mm. When the thickness of the first spacing part is0, the spacing part does not exist, and when the thickness exceeds 20mm, the intensity of light reduces, and it is problematic thatreliability as a lighting device cannot be secured.

FIG. 3 is a view illustrating a structure 100 c in which the secondoptical member and an optical sheet are added to the lighting deviceaccording to the embodiment illustrated in FIG. 1.

Referring to FIGS. 1 to 3, a lighting device 100 c according to stillanother embodiment of the present invention may further comprise: afirst optical sheet 170 that is formed between the resin layer 150 andthe second optical member 290 and is formed on the upper surface of theresin layer 150; a second optical sheet 190 formed on the first opticalsheet 170; and an adhering layer 180 disposed between the first opticalsheet 170 and the second optical sheet 190. A second spacing part 181may be further formed at the adhering layer 180. In other words, theadhering layer 180 forms a space (second spacing part 181) around anoptical pattern 183, and an adhering substance is coated on the otherportions, so the first optical sheet 170 and the second optical sheet190 are adhered to each other.

In addition, the optical pattern 183 may be further formed on an uppersurface of the first optical sheet 170 or a lower surface of the secondoptical sheet 190, and at least one optical sheet may be further formedon the second optical sheet 190. The structure formed of the firstoptical sheet 170, the second optical sheet 190, the adhering sheet 180and the optical pattern 183 can be defined as an optical pattern layerA. In a case where the second optical sheet 190 and the first opticalsheet 170 form a double layer structure by providing the second opticalsheet 190, an air layer is formed around the optical pattern, and thuslight passing through the resin is again scattered due to an air layerhaving a different refractive index, thereby improving a light diffusionproperty. In a case where the adhering layer serves as a spacer, whichforms the air layer while being formed in a structure which surroundsthe peripheral portion of the optical pattern, a light shielding effectcan be realized by the optical pattern and a light diffusion effect canbe implemented at the peripheral portion. Also, when there is no airlayer, the light shielding effect is remarkably reduced.

Also, the optical pattern 183 formed on the upper surface of the firstoptical sheet 170 or the lower surface of the second optical sheet 190may be formed of a light shielding pattern so as to inhibit the lightfrom the light emitting unit 160 from focusing. For this, it is neededto align between the optical pattern 183 and the light emitting unit130. The first optical sheet 170 and the second optical sheet 190 areadhered using the adhering layer 180 so as to obtain a stable fixingforce after the aligning procedure.

The first optical sheet 170 and the second optical sheet 190 may be madefrom materials having high light transmissivity, for example, they canbe made from PET as one example.

The optical pattern 183 disposed between the first optical sheet 170 andthe second optical sheet 190 serve to inhibit the light from the lightemitting unit 130 from not focusing. The light shielding pattern may beprovided to produce a partial light shielding effect so as to inhibitthe optical characteristics from worsening owing to too high intensityof light or the yellow light from becoming yellowish. The abovementioned light shielding pattern can be formed by means of a printingprocess on the upper surface of the first optical sheet 170 or the lowersurface of the second optical sheet 190 using a light shielding ink.

The optical pattern 183 may be configured to adjust the light shieldingdegree or diffusion degree using one optical pattern so that the lightcan be fully shielded or part of the light can be shielded along withthe light diffusion function. More specifically, the optical pattern 183of the present invention may be implemented in a double printingstructure of a combined pattern. Here, the structure of a doubleprinting structure represents a structure formed as one pattern isformed, and then another pattern is formed on the same.

According to the present embodiment of the invention, the opticalpattern 183 may be in the double structure of a diffusion pattern formedon a lower surface of a polymer film (for example, second optical sheet)in the emitting direction of light using a light shielding inkcontaining at least one among TiO₂, CaCO₃, BaSO₄, Al₂O₃, silicon, etc.and a light shielding pattern formed using a light shielding inkcontaining Al or a mixture of Al and TiO₂. The double structure of theoptical pattern is intended to efficiently control a hot spot phenomenongenerated due to the light emitted from the light source such as LED.Thanks to the structure, a more stable light shielding effect comparedto the light shielding pattern formed in a printing structure of FIG. 1can be implemented. Also, since the thickness which can be implementedby a printing process is limited, by implementing different patternshapes from each other using a plurality of printing processes, thepattern shapes are adjusted depending on a distance from the LED togenerate a partial difference in thickness among the patterns, so thatthe light shielding efficiency can be improved.

That is, after a diffusion pattern is white-printed on the surface ofthe polymer film, a light shielding pattern may be formed on it, and onthe contrary, the double structure may be formed in the sequenceopposite to it. When the double printing structure corresponds to thestructure in which after the diffusion pattern is white-printed on thesurface of the polymer film, the light shielding pattern is formed onit, or the structure opposite to the structure, thanks to existence ofthe light diffusion pattern, penetrating light is not completelyshielded and light filtered by the light shielding pattern can bediffused upward, thereby increasing efficiency for light utilization.

It is obvious that the formed design of such patterns may change invarious forms depending on the efficiency, intensity and light shieldingratios of light. Alternatively, there may be provided a triple structurein which a light shielding pattern formed of a metallic pattern isformed at the center of the sequential stacking structure and thediffusion pattern is formed at the upper side and the lower side,respectively. The above mentioned triple structure could be implementedby selecting one of the above mentioned materials. Preferably, one ofthe diffusion patterns may be formed using TiO₂ having a good refractiveindex. Another diffusion pattern may be formed using CaCO₃ having a goodoptical stability and a good-looking color along with TiO₂. Theefficiency and uniformity of light can be obtained with the aid of thetriple structure which implements the light shielding patterns using Alwhich has a good hiding function. In particular, CaCO₃ has a function ofproviding white light with the aid of a function of reducing theexposure of yellow light, thus obtaining more stable illuminatingeffects. An inorganic material having a larger particle size and asimilar structure such as BaSO₄, Al₂O₃, silicon bead, etc. except forCaCO₃ could be applied. In addition, it is preferred that the opticalpattern 183 is formed to have a good illuminating efficiency byadjusting the pattern density so that the pattern density gets lower asit becomes farther from the emitting direction of the LED light source.

The adhering layer 180 may be formed in a structure that the peripheralportion of the optical pattern 183 is surrounded, and a second spacingpart 181 is formed at the other portions or in a structure that a secondspacing part 181 is formed around the optical pattern 183. So, analignment can be obtained by adhering two optical sheets. In otherwords, the adhering structure of the first optical sheet 170 and thesecond optical sheet 190 serves to fix the printed optical patterns 183.

At this time, the adhering layer 180 may be made from a thermosettingPSA, a thermosetting adhesive or a UV curable PSA type substance, but itis not limited to them.

As shown in FIG. 3, the first spacing part 280 may be formed between thesecond optical sheet 190 and the second optical member 290. Tanks to thepresence of the first spacing part 280, the uniformity of the lightsupplied to the second optical member 290 can be enhanced, andconsequently, the uniformity of the light diffused and emitted by way ofthe second optical member 290 can be enhanced. At this time, thethickness H1 of the first spacing part 280 may be formed in a range of 0to 20 mm in order to minimize the deviations of the light which passesthrough the resin layer 150, but it is not limited thereto. Ifnecessary, it can be changed properly depending on the necessities asshown in FIG. 4. Thanks to the existence of the first spacing part,light passing through the optical member 150 and the optical patternlayer penetrates mediums having different refractive indexes whilepassing through the air layer of the spacing part once again so that alight diffusion property or a light scattering property can be improved,and then the light again penetrates the mediums having the differentrefractive indexes through the second optical member so that theuniformity of the diffused and scattered light can be improved.

The second optical member 290 is formed in a fragment to be disposedonly at the upper portion of the LED so that the LED can be covered fromthe outside. As a result, the appearance of the light device can getbetter during lighting or black out, and the surface light emission canbe performed. A surface light emission effect is generated at a portionwhere the LED does not exist.

As not shown in the drawings, at least one optical sheet can be furtherformed on the optical pattern layer “A” if needed.

FIG. 4 is a schematic view illustrating a structure in which a lightingdevice according to the one embodiment of the present invention isapplied to a headlight for a vehicle.

As shown in FIG. 4, the lighting device 100 a according to the oneembodiment of present invention is formed using a flexible circuit boardand a resin layer, so the lighting device itself has flexibility. Asshown in FIG. 6, thanks to such flexibility, the present invention canbe easily applied to the headlight housing 300 for a vehicle with curvedsurfaces. The degree of design freedom for the sake of a finishedproduct engaged with the housing can be enhanced. Separate from theeffect and design freedom, uniform brightness and luminance can beobtained. FIG. 4 shows that the lighting device illustrated in FIG. 1 isengaged, but it is provided only for an illustrative purpose, and thelighting device illustrated FIG. 2 or 3 may be engaged.

FIG. 5 is a view illustrating an actual operation state image at thefront view, bottom view and lateral view of the lighting deviceaccording to the one embodiment of the present invention. As shown inFIG. 5, thanks to the protruding optical patterns, the shapes of lightcan visually change depending on the viewing angle when viewing thelight source.

As the present invention may be embodied in several forms withoutdeparting from the spirit or essential characteristics thereof, itshould also be understood that the above-described examples are notlimited by any of the details of the foregoing description, unlessotherwise specified, but rather should be construed broadly within itsspirit and scope as defined in the appended claims, and therefore allchanges and modifications that fall within the meets and bounds of theclaims, or equivalences of such meets and bounds are therefore intendedto be embraced by the appended claims.

What is claimed is:
 1. A lighting device, comprising: a printed circuitboard; a resin layer disposed on the printed circuit board; a lightingemitting unit disposed on the printed circuit board; and a first opticalmember disposed in contact with the resin layer, wherein the firstoptical member comprises a base member and a plurality of protrusionoptical patterns disposed on the base member, wherein the plurality ofprotrusion optical patterns is disposed on a first surface of the basemember and the resin layer is disposed on a second surface opposite tothe first surface of the base member.
 2. The lighting device of claim 1,wherein the resin layer comprises a plurality of light diffusers.
 3. Thelighting device of claim 2, wherein the plurality of light diffusers isselected from the group consisting of silicon, silica, glass bubble,PMMA, urethane, Zn, Zr, Al2O3, and acryl.
 4. The lighting device ofclaim 1, comprising a reflection member disposed between the resin layerand the printed circuit board.
 5. The lighting device of claim 4,comprising a plurality of a reflection patterns disposed on thereflection member.
 6. The lighting device of claim 4, wherein thelighting emitting unit is arranged to penetrate the reflection member.7. The lighting device of claim 6, wherein the lighting emitting unitcomprises a plurality of light emitting diodes, wherein the plurality oflight emitting diodes are side view type.
 8. The lighting device ofclaim 4, comprising a second optical member disposed on an upper portionof the resin layer.
 9. The lighting device of claim 8, wherein a firstspacing part is disposed between the resin layer and the second opticalmember.
 10. The lighting device of claim 9, wherein the first opticalmember is disposed between the first spacing part and the reflectionmember.
 11. The lighting device of claim 1, wherein a side surface ofthe protrusion optical pattern and the first surface of the base memberform an acute angle.
 12. The lighting device of claim 11, wherein across-sectional shape of the protrusion optical pattern comprises atriangular shape.
 13. The lighting device of claim 1, wherein the resinlayer is formed of an ultraviolet ray thermosetting resin containingoligomer, and wherein the oligomer contains any one material selectedfrom the group consisting of urethane acrylate, epoxy acrylate,polyester acrylate, and acrylic acrylate.